Ira Bowen at work with a vacuum spectrograph at Caltech. Work with this instrument was started at the University of Chicago in 1916 by Dr. Robert Millikan. It has been at use at Caltech since 1933. Investigations have been carried on in the structure of individual atoms such as flourine, chlorine, chromium, manganese and iron.

ID number

1.2.2-2

Title

Paul Dirac, Robert Millikan and J. Robert Oppenheimer

Abstract

Physicists - Group

ID number

50.6-1

Title

Robert Millikan with Millikan-Neher self-recording ionization chamber

Abstract

This electroscope was designed to measure cosmic ray intensity.

ID number

1.22-10

Title

Cosmic-ray research at Fort Sam Houston, TX

Abstract

Weighing off one of the 2.5m balloons. Temporary guys to the top lug made the management much easier and safer.